Let s,-1t2 for n n. then which one of the following is true for the sequence (s,) (a) s.converges in q (b) s,) is cauchy sequence but does not converge in (c) t

Let S,-1T2 for n N. Then which one of the following is True for the sequence (s,) (A) s.converges in Q (B) s,) is Cauchy sequence but does not converge in (C) the subsequence (s., is convergent in R, only whenk is even natural number D) S.is not a Cauchy sequence